What Do You Need To Know About Polydactyly? 

Polydactyly is a congenital condition. If a baby is born with more than the usual number of fingers or toes it is called polydactyly. Instead of 5 fingers, each hand or foot may have 6 or more fingers. This extra digit can vary in size and be a fully functional or partially formed soft fragment. The condition can be part of a genetic syndrome that affects both hands or feet. It can be seen in approximately one in every 1000 live births. Can this condition be seen in your child? Wait to get more details about polydactyly. 

• What are the common types of polydactyly?

1. Preaxial polydactyly – The extra finger or toe is on the thumb side of the hand or the big toe side of the foot. However, it is less common than postaxial polydactyly. 
2. Postaxial polydactyly – The extra digit is on the pinky side of the hand or the little toe side of the foot. The postaxial polydactyly is the most common type.
3. Central polydactyly – The extra digit is located between the other finger or toes, not on the edges. However, it is a rare type of polydactyly. 

• What causes polydactyly?

The various factors cause polydactyly. Primarily it is related to genetic factors and the development process. Here are some factors. 

Genetic factors

Inheritance – Polydactyly is often inherited in an autosomal dominant pattern. That means a baby often inherits it from a parent with the condition. And if a parent has polydactyly, their baby has a 50% chance of developing it.

Gene mutations – Specific gene mutations affecting the GL13 gene lead to polydactyly. These genes play a major role in the development of hands and feet during embryonic development. 

Sporadic occurrence

De Novo mutations – Polydactyly conditions may occur sporadically in families with no history of polydactyly due to new mutations or genetic changes occurring during fetal development. 

Associated syndromes

Genetic syndromes – Some genetic syndromes such as Ellis-van Creveld syndrome, Bardet-Biedl syndrome, or Rubinstein-Taybi syndromes may cause polydactyly. In these cases, polydactyly is one of the several symptoms that occur together. 

Environmental factors – Factors such as exposure to various chemicals and drugs during pregnancy, especially when combined with a genetic predisposition, can influence polydactyly conditions. However, it is less common. 

Development abnormalities

Limbud development – Abnormalities in the early stages of embryonic development also cause polydactyly.

Polydactyly is most commonly due to genetic factors. However, it can also be part of a broader syndrome or sporadically.  

• Can you see polydactyly on an ultrasound?

Yes, polydactyly can often be detected on an ultrasound. It can be typically identified during the trimester, around the 18-20 week mark. However, it is uncommon to diagnose polydactyly before the birth of the baby. 

• What are the treatments?

Surgery – The most common treatment for polydactyly is surgery. If the extra digit is nonfunctional or causes issues with movement or fitting things, it should be removed.  The surgery involves removing the extra digit. Besides it is reconstructing the hand or foot if necessary. Besides, the complexity of the surgery depends on whether the digit contains bones, joints, and tendons or is just soft tissue.  

Ligation – Used for small, soft-tissue extra digits. It is often referred to as “Pedunculated” digits which are attached by a narrow stalk of tissues. Here, a ligation is tied around the extra digit, and the blood supply is cut off and falls off naturally over time. This is usually done shortly after birth. Besides, the procedure is simple and painless. 

Observation – The extra digit may not be removed if it is not causing problems and is not fully grown. There is no need to remove those fingers if they are not involved in additional activities or appearance. 

Reconstructive surgery – More extensive reconstructive surgery may be necessary when the extra digits are important for activities or if there are other associated abnormalities. This improves the appearance, function, and alignment of the affected arm or leg and ensures that it functions normally. 

Physical therapy – Physical therapy might be recommended to help improve strength, flexibility, and function after surgery. 

• What is the best age for polydactyly surgery?

Doctors say that it is best to do this simple surgery in the first three months from the birth of the baby. The reason for this is the low movements of the babies during this age limit. And during this time, babies can be kept still for a numbing anesthetic instead of anesthesia. However, this period may vary from child to child. Some babies are strong at three months and cannot be held in the same position. 

Doctors do not recommend the “tying off” option with sutures. Why? This is because lumps can sometimes remain and become painful over time. Therefore, use a scalpel to create a smooth contour and flat scar on the hand. 

• Is refusing surgery an option? 

Do not remove the extra digit especially when it does not interfere with the function. Leave it unremoved, at least until the baby can decide whether to remove it, then it can be removed by surgery. 

Conclusion 

What do you know about polydactyly? It is a common congenital anomaly and can vary widely in its presentation. Due to some genetic inheritance and developmental abnormalities, polydactyly can occur. Besides, sometimes associated syndromes and sporadic occurrences also cause polydactyly. There are three types of polydactyly. They are preaxial, postaxial, and central polydactyly. Out of those three types, the most common one is post polydactyly and the rare type is central polydactyly. 

Polydactyly can be removed by using surgery. It can usually be removed by the time the baby is three months old. However, if it does not affect the normal functioning of the child, then leave it until the child is old enough to understand. Then the child will decide whether to remove it. It can be removed surgically if the child wishes to have it removed. Here we have provided more information about polydactyly. However, you can refer to more medical research papers for further details. If your baby has an extra digit, please visit a doctor for advice.